(昆明理工大學(xué) 冶金與能源工程學(xué)院，昆明 650093)
摘 要: 濕法煉鋅過程產(chǎn)出的鐵礬渣含有大量的有價金屬鋅、鉛以及伴生金屬鐵，在水熱條件下，危廢鐵礬渣將發(fā)生高效分解與轉(zhuǎn)化，有價金屬轉(zhuǎn)入溶液，伴生鐵轉(zhuǎn)化為赤鐵礦。本文以濕法煉鋅企業(yè)產(chǎn)出的鐵礬渣為研究對象，研究了反應(yīng)溫度、反應(yīng)時間、液固比、初始酸度、晶種濃度等宏觀技術(shù)參數(shù)對鐵礬渣分解與轉(zhuǎn)化的影響規(guī)律。理論計算和實(shí)驗(yàn)結(jié)果均表明在高溫水熱體系中，鐵礬渣中的黃鉀鐵礬、黃銨鐵礬和鐵酸鋅物相均可有效轉(zhuǎn)化為赤鐵礦，而鉛鐵礬性質(zhì)穩(wěn)定不易轉(zhuǎn)化。升高溫度并延長反應(yīng)時間有利于黃鉀鐵礬、黃銨鐵礬和鐵酸鋅物相的水熱分解與轉(zhuǎn)化。在220 ℃下反應(yīng)1 h后，鐵礬物相轉(zhuǎn)化基本完成，其轉(zhuǎn)化率達(dá)94%；反應(yīng)4 h后鐵酸鋅物相衍射峰完全消失，鋅浸出率達(dá)87%，轉(zhuǎn)化渣中赤鐵礦含量達(dá)68%。適當(dāng)提高初始酸度有利于鐵酸鋅的轉(zhuǎn)化，但當(dāng)體系初始酸度高于15 g/L時將抑制鐵礬物相轉(zhuǎn)化。在反應(yīng)溫度220 ℃、反應(yīng)時間4 h、液固比(mL/g) 10:1、初始酸度0.01 g/L的條件下，鋅浸出率為89%，鐵礬物相的轉(zhuǎn)化率可達(dá)95%，鐵礬轉(zhuǎn)化渣中主要物相為赤鐵礦，其含量為68%。
關(guān)鍵字: 鐵礬渣；水熱分解；赤鐵礦；轉(zhuǎn)化行為
（Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China）
Abstract:The jarosite produced in the process of zinc hydrometallurgy contains a large amount of valuable metal Zn, Pb and associated metal Fe. Under hydrothermal conditions, the jarosite will decompose and transform efficiently, the valuable metal will be transferred into solution, and the associated Fe will be transformed into hematite. In this paper, the jarosite produced by the zinc-iron separation process in the wet zinc smelting enterprise was taken as the research object, the effects of macroscopic technical parameters such as reaction temperature, reaction time, liquid-solid ratio, acidity and crystalline concentration on the decomposition and transformation of jarosite and zinc ferrite phases in precipitates were studied. Theoretical calculation and experimental results show that in high-temperature hydrothermal system, jarosite, ammoniojarosite and zinc ferrite phase in jarosite slag can be effectively transformed into hematite, while the plumbojarosite are stable and difficult to be transformed. Increasing the temperature and prolonging the reaction time are beneficial to the hydrothermal decomposition and transformation of the phase of jarosite, ammoniojarosite and zinc ferrite. After reaction of 1 h at 220 ℃, jarosite phase transformation is basically completed, the conversion rate is 94%; and after the reaction of 4 h, the diffraction peak of zinc ferrite phase disappears completely, zinc leaching rate is 87%, and the transformation of precipitates in hematite content is 68%. Appropriately increasing the acidity of the system is conducive to the transformation of zinc ferrite, but when the initial acidity of the system is higher than 15 g/L, the phase transformation of ferrite will be inhibited. Under the conditions of reaction temperature of 220 ℃, reaction time of 4 h, liquid-solid ratio(mL/g) of 10:1, and initial acidity of 0.01 g/L, the zinc leaching rate is 89%, the conversion rate of jarosite phase can reach 95%. Hematite is the main phase in precipitates, and its content is 68%.
Key words: jarosite; hydrothermal decomposition; hematite; transformation behavior
